I'm agreeing with everyone else. Do absolutely nothing until 1/16. I wouldn't even ask HR questions.
You could have some kind of meltdown on 1/16, say "I quit", and leave in a tizzy. A few weeks later, call up and apologize, say you had a breakdown due to personal stuff, are in therapy, etc.. Thank them for all the good times. They'll be happy they don't have to carry you while you're out on extended medical leave. They'll be seriously afraid to say anything negative to referrals (HIPAA, ADA, etc.). Years later you can get hired again.
Been there, seen that.